Frame tightener



FIG. 1 is a perspective view of a frame tightener according to my new design.

FIG. 2 is a front end view thereof.

FIG. 3 is a right side elevational view thereof, the left side elevational view being a mirror image.

FIG. 4 is a top plan view thereof, the bottom plan view being a mirror image.

FIG. 5 is a rear end view thereof; and,

FIG. 6 is an exploded, perspective view thereof.

The broken lines in the drawings illustrate portions of the frame tightener and form no part of the claimed design. 

CLAIM The ornamental design for a frame tightener, as shown and described. 